Rotary engine.



R. P. SCHMIDT. ROTARY ENGINE.

APPLICATION FILED M0523, 1907.

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ROTARY ENGINE.

APPLICATION FILED DBO. 23, 1907.

4Patented Nov. 2, 1909.

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Ri. P. 'sc lHMIDir. ROTARY ENGINEME APPLIOATION FILED DEO. 23, 1907.

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ROTARY ENGINE. APPLIOATIOINI FILED DEG. 23,'1907. y

Patented Nov* 2,1909.

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' abutment.

RUDOLPH F. SCHMIDT,OF CINCINNATI, OHIO.

ROTARY ENGINE.

Specification of Letters Patent.

Patented Nov. 2,1909.

Application filed December 2.3, 1907. Serial No. 407,653.

To all whom it may concern:

Be it known that I, RUDOLPH F. SCHMIDT,

a citizen of the United States, residing at Cincinnati, in the county ofHamilton and State of Ohio, have invented certain new and usefulImprovements in Rotary Engines, of which the following is a specication.

My invention relates to motive power apparatus, the object being toprovide a prime mover of simple construction and eii'icient inoperation.

My invention consists in the parts and in the details of constructionand arrangement of parts as will hereinafter be more fully described andclaimed.

In the drawings: Figure 1 is an end elevation of an engine embodying myinvention, part of the bearing standard being represented as broken awayfor the purpose of clearness of illustration. Fig. 2 is a detailperspective view of one of the piston heads. Fig. 3 is a detailperspective view of one of the pivoted abutments. Fig. t is a sectionaldetail view illustrating the construction of the spring plates forforming steam tight joints between the walls of the casing and thepivoted abutments and piston heads. Fig. 5 is a detail view illustratingthe spring mechanism for operating the pivoted abutment levers, thespring casing being shown in section on a line corresponding to we-fw ofFig. 11. Fig. 6 is a cross section, on a line corresponding to jz/-y ofFig. 11 of one of the engines, the base being omitted. Fig. 7 is apartial enlarged sectional view on a line corresponding to the line zroof Fig. 6 better illustrating the arrangement of the packing ringadjustment mechanism. Fig. 8 is a section on the line z-.e of Fig. 1 ofpart of the steam inlet apparatus, better illustrating the constructionof the inlet valve and the casing therefor. Fig. 9 is a detailperspective view of a cam wheel for operating the pivoted Fig. 1() is adetail plan view of the hinged plate forming part of the spring cushionfor the pivoted abutment. Fig. 11 is a partial side elevation andsection of my invention, the section being taken on a line correspondingto ccof Fig. 1. Fig. 12 is an enlarged end elevation of part of theengine, parts being broken away for better illustrating the actuatinggear for the abutment member and the mechanism for holding the gear andabutment member out of operative position, which position is representedby dotted lines. Fig. 13 is a section on the line a-a of Fig. 12,showing how the lever is secured on the squared end of the shaft of theabutment member. Fig. 14 is a detail perspective view of the forkedbracket for sustaining the spring casing. Fig. 15 is a side elevation ofpart of the forked rod.

My invention as illustrated consists in two complete engines operating avsingle shaft 1, each of these engines consisting in a cylinder 2concentric with the shaft 1, within which the piston wheel 3 is rigidlymounted on the shaft 1 by means of a key l. The cylinder 2 is closed bymeans of the plate 5, which is secured by means of tap screws 6 takinginto flanges on the cylinder. The hub 7 of the piston wheel 3 ispreferably of less width than the rim 8, and the cylinder wall 9, aswell as the plate 5, are indented so that they form end-thrust bearingsfor the hub 7.

vl here the shaft 1 passes through the wall 9 and plate o, suitablestuffing boxes 10 and 11, respectively, are provided to prevent theescape of any steam which may pass the rim 8 of the piston wheel, whichrim 8 is provided with stationary packing rings 12 and 13. These packingrings 12 and 13 are embedded in annular recesses in the cylinder wall 9and plate 5, respectively, and also take into the sides of the rim ofthe piston wheel 3, which rim is provided with corresponding annularrecesses to receive the packing rings.

For the purpose of uniformly adjusting the packing rings against thepiston wheel throughout their circumference, I provide each packing ringwith a series of set screws 14, each of which is provided with a pinion15, these pinions all being in mesh with a gear 16 mounted looselyconcentrically with the shaft 1, so that when one of the set screws 14is turned to clamp the packing ring, all of the other set screws bearingagainst the packing ring will be simultaneously turned an equal amount.

Mounted on the rim of the piston wheel 3, in a suitable recess 17therein, is the piston head 18 secured by tap screws 19 and 19a. Thispiston head 13 conforms to the inner concave surface of thecylinder 2 inits main part 20, from which main part 20 it is inclined in bothdirections circumferentially of the piston wheel 3. The main part 2O isprovided with spring lplates 21 which are mounted in slot-s in the sidesof the piston head, these slots being cut at an angle. to the sides, andthe spring plates 21 being beveled to make uniform contact with thewalls of the cylinder casing constituted by the wall 9 and the plate 5,thus making steam tight joints at the sides of the piston head. Eachplate is held in its slot by a screw 21a and pressed outward against thewall of the cylinder casing by a spring 21b which is confined in arecess 21C.

VFor admitting steam to the cylinder, a valve casing 22 is formedintegral therewith, and a steam port 23 leads from the interior of thevalve casing to the interior of the cylinder casing. lVithin this valvecasing 22 the cylindrical valve 24 is mounted and accurately tted to theinterior of the valve casing. This cylindrical valve 24 has the rockshaft 25, preferablyV formed integral therewith, and a conical bearingis formed on the end of the cylindrical valve adjacent to its junctionwith the rock shaft 25, while the plate 26 closing the end of the valvecasing and the part of the valve casing adjacent to. the plate 26, arecorrespondingly recessed to receive the conical bearing of thecylindrical valve. At the other end of the valve casing 22, a plain flatplate 27 holds the cylindrical valve 22 in the valve casing, and theparts being accurately fitted, the cylindrical valve is prevented fromend play thereby. A suitable stuffing box 28 is provided in the plate 26where the rock shaft 25 extends through it. The steam enters the valvecasing 22 at its top through a suitable shaped opening 22a therein, thetop of the valve casing being provided with a flange 29 to which theflange of the steam pipe 30 is bolted. The cylindrical valve 24 isprovided with a segmental slot 24a adapted to aline with the opening, sothat steam may enter the interior of thercylindrical valve. Thiscylindrical valve is also provided with segmental slot 24", which isadapted to aline with the steam port 23.

The pivoted abutment 31 is mounted in the chamber 32, which is incommunication with the interior of the cylinder 2 and is closedoutwardly by means of a cover 33 bolted onto the cylinder casing. Theexhaust outlet 34 is adjacent to the chamber 32 and leads from theinterior of the cylinder casing, out- Y side of which the exhaust pipe35 is bolted to the casing, in alinement with the exhaust outlet.Preferably the steam port 23, chamber 32 and exhaust outlet 34 areplaced as closely adjacent as is consistent with the provision of aproper amount of bearing surface for the piston head between theseopenings. The pivoted abutment 31 is mounted on a shaft 36 taking.through the wall 9 and the plate 5 of the cylinder casing where theshaft is provided with suitable stutling boxes 37 and 38, respectively.Positive rigid connection is insured between the pivoted abutment 31 andthe shaft- 36 by means of suitable pins taking through the pivotedabutment and shaft and held in place by a plate as illustrated at 36a inFig. 6. The lowei side of the pivoted abutment 31 is adapted to engagewith the piston head 13 and with the periphery of the piston wheel 3 andforni a steam tight joint with them. The free end of the pivotedabutment 31 is curved concentrically to the shaft 36, and a springpacking plate 39 is secured on one wall of the chamber 32 and bearsagainst the curved free end of the pivoted abutment 31 to form a steamtight joint therewith, this plate extending entirely across the chamber32. Plates, similar to the plates 22 on the piston head, are provided onthe sides of the pivoted abutment 31 and bear against the cylinder' wall9 and plate 5 to form steam tight joints therewith. The pivotedVabutment 31 is recessed on its upper surface merely for the purpose ofmaking it lighter.

The piston head 13 is provided with re-k cesses or pockets 40, whichserve the double purpose of making it light in construction andreceiving the steam at the beginning of the operation. Thus when thebody part 20 of the piston head 18 has passed they steam port 23, thepivoted abutment 31 is designed to contact with the piston head,

and the cylinder valve 22 being properly operated, steam will beadmitted between the area of contact of the piston head 13 with theinner concave surface of the cylinder casing and the contact of thepivoted abutment 31 with the piston head, so that the piston wheel 3,and consequently the shaft 1, will be rotated by the expansive force ofthe steam acting between the piston head 18 and the pivoted abutment 31.The force of the steam will continue to be utilized during therevolution of the piston' wheel 3 until the contacting part of thepiston head 18 has passed the outlet opening 34, when the exhaust willbe released to the atmosphere. F rom this point until the piston headcan reach its initial position as above described, the momentum of themoving parts may be depended upon, after which the operation will berepeated.

The piston heads on the piston wheels of the two engines in the pair areoppositely positioned so that a balanced action is secured, while therecovery of one engine isY rendered positive by the expansive force ofYthe steam acting in the other engine, the i valve 22 of which will befully open at the time. For the purpose of properly operat-V ing thecylindrical valve 22, a rocker arm 41 is rigidly mounted on the rockshaft 25 by i screws 44a and is connected to the wrist pin 43 by meansof a suitable rod 45 provided with the well known strap and wedgeadjustment 46. This eccentric is so set that the segmental opening 24bin the cylindrical valve 24 will approach the valve casing` end of thesteam port 23 as the piston head approaches the cylinder casing end ofsaid port, but will not allow steam to be admitted to the cylindercasing from the valve casing until the pockets in the piston head havepassed from under the contacting part of the pivoted abutment 31. thusobviating the raising of the pivoted abutment by the engagement of thelive steam with its under or contacting surface, which would otherwiseresult and cause a loss of steam, since that part of the cylinder casingon the opposite side of the pivoted abutment 31 communicates directlywith the exhaust outlet 34. `With the eccentric thus set and the variousparts proportioned as illustrated in the drawings, the live steam willbe admitted during less than half the revolution of the piston wheel 3,when the cylindrical valve 24 will have been rotated backward until thecommunication between the segmental opening 24b and the steam port 23 isagain broken and the admission of live steam terminated. From this pointthe expansive force of the amount of steam thus admitted to the cylinderis utilized until the piston head reaches the exhaust outlet as abovedescribed. It will thus be seen that with a valve gear of suchconstruction, economical use of the steam is attained, while the forceof the steam is applied in the most effective and direct manner to theshaft 1 throughout almost its entire revolution.

In order to obviate the necessity of raising the pivoted abutment 31 bythe contact of the inclined surface of the piston head 18, l provide a`cam wheel 47 rigidly mounted at the shaft 1 by means of the countersunkscrews 48 and adapted to actuate the pivoted abutment by means ofbalancing levers 51 and 54 connected by links 53 to compression spring56. The plate 49 is bolted to the outside of the cylinder casing, and inthis plate is secured a stud 50 on which is pivoted the bell crank 51.One member of this bell crank 51 is preferably provided with a bears ingblock 52 which is adapted to engage with the periphery of the cam wheel47, while the other member has pivoted to it the link 53 which is alsopivoted to one end of the lever 54, and which lever is rigidly securedto the shaft 36 of the pivoted abutment 31. On account of the somewhatsevere strain imposed during the operation of the engine at high speedin the raising of the pivoted abutment by the above described mechanism,I prefer to square the end of the shaft 36 and provide the lever 54 witha square hole to receive the squared end of the shaft 36, the

lever being held thereon by means of a set screw 55, as is best shown inFig. 13 of the drawing.

The periphery of the cam wheel 47 is concentric with the shaft 1, uponwhich it is mounted, throughout such a proportion of its extent that thebearing block 52 which engages therewith, and consequently the bellcrank 51, link 53, lever 54, shaft 36 and pivoted abutment 31 willremain stationary, and the pivoted abutment 31 will make contact withthe periphery of the piston wheel 3, until the piston head 18 closelyapproaches the pivoted abutment 31, when the bearing block 52 will beengaged by the eccentric part of the periphery of the cam wheel. 47 andbe gradually forced outward, away from the shaft 1. This eccentric partof the periphery of the cam wheel thus forces the bearing block 52outward at such a rate that the contacting part of the pivoted abutment31 is raised away from the periphery of the piston wheel 3 more rapidlythan the surface of the circumferentially inclined end of the advancingpiston head 18 rises to make contact with it. lVhen the main part 20 ofthe piston head 18, which is concentric to the shaft 1, has been carriedunder the abutment 31, the eccentric part of the periphery -of the camwheel 47 terminates, and the periphery of the cam wheel takes adirection substantially radially of the shaft 1, thus allowing thebearing block 52 to abruptly approach the shaft 1, and the pivotedabutment 31 to abruptly make contact with the piston head 18. Asillustrated in the drawings, the pivoted abutment has just accomplishedthis contact, and as will be noted, the extended portion of the camwheel has passed away from the bearing block 52 of the bell crank 51,leaving the entire pivoted abutment actuating mechanism supported by thecontact of the pivoted abutment with the piston head. The various partsof this mechanism are so proportioned that they almost balance thepivoted abutment 31 thus adding to the ease of operation. By providingmeans for raising the pivoted abutment independently of its contact withthe piston head, the undesirable violence of contact between the pivotedabutment and piston head, which would otherwise be encountered duringrapid rotation of the piston wheel, is eliminated. A spring cushion isprovided for the pivoted abut-ment consisting in a plate hinged at 31a,this plate having one of its members bolted onto the under side of thecover 33, while the other member adjacent to the free end of the pivotedabutment 31 has spiral springs such as 31b inserted between it and theunder side of the cover 33, these springs being held in place bysuitable lugs on the under side of the cover 33 and on the upper side ofthe member of the hinged plate. Thus the pivoted abutment is fully undercontrol during its movement in either the upward or downward directionand Violent contact of any of the parts prevented.

For allowing positive adjustment of the contact of the pivoted abutmentwith the periphery of the piston wheel and with the piston head, Iprefer to provide a compression spring 56, which is inclosed in a springI casing 57, and acts on the pivoted abutment actuating mechanismthrough the medium of the rod 58 which is pivoted to the link 53, andpassing through the lower closed end of the spring casing 57 issurrounded by the lspring 56 and is provided with a washer 59 inengagement with the upper end of said spring above which is a nut 60 forregulating the action of the spring. The spring casing is provided withtrunnions 61 which bear in a forked bracket 62 bolted onto the cylindercasing.

vWhere the engine is to be used for marine purposes or any other usewhere a reverse motion may be required, duplicate sets of enginesdirectly connected on the same shaft are provided, one of the sets beingdesigned to operate in one direct-ion and the other to operate in theopposite direction, and each of the engines is provided with a suitableforked rod 5421 adapted to embrace the lever 54 and be raised so thatthe crotch 54b of the fork is out of engagement with the lever 54 andallows the reciprocation of the lever in the operation of the engine.Vhen this rod is depressed, the crotch 54b will engage with the lever 54and depress it, raising the pivoted abutment 31 out of position forengagement with the piston head 18 and removing the bea-ring block 52 ofthe bell crank 51 out of position for engagement with the cam wheel 47,and allowing the engine to be freely rotated backward by the duplicateset of engines. For holding the forked rod 54 in either raised orlowered position, a lever 54'3 may be provided, having a lockingmechanismadapted to engage with a sector 54, in which the lever ispivoted, as illustrated in Fig. 12 of the drawing. This lever may belocated at any convenient position and at some distance from the engineif desired. As the bell crank 51 may be actuated by the cam wheel 47only by the engagement of its bearing block 52 therewith, and is thusnot positively connected to the cam wheel, the convenient raising of theabutment member 31 by means of the forked rod 54h embracing the lever 54is facilitated in a manner especially desirable Where it is required toquickly reverse the engines, and where the operator must be at somedistance from the engines.

lhile the device above described for retaining the pivoted abutment andits actuating mechanism out of operative position is desirable andobviates all unnecessary contact of the parts, it will be noted that theengine may be freely rotated backward without this provision` since thepiston head 18 is provided with the inclined surface which serves tosupport the pivoted abutment in its descent during the forward motion,and will raise it with equal facility during thereverse motion.

As illustrated, I prefer to provide each engine with a complete set ofpivoted abutment actuating mechanism, as above described, on each sidein order to prevent twisting strain on the shaft 36, while only one setof valve gears is provided for each engine, this valve gear hereinbeforedescribed being adjacent to the bearings 1a of the shaft 1.

Suitable drain pipes 63 are provided for each engine and are providedwith valves 64. The cylinder casings of the two engines in the pair aresupported on a bed plate 65 by means of feet 66 and secured together andbraced by means of the arc shaped spacing piece 67 as well as by anadditional spacing piece 68. The bearing standards 69 supporting thebearings 1a are bolted to the bed plate 65, as are the feet 66 of thecylinder casing. The pulley 70 mounted on the shaft 1 between the twoengines may be used for operating a suitable governor to regulate thesupply of steam to the engine. This governor may be of any of the wellknown constructions used with reciprocating engines. By locating all ofthe valve gear, pivoted abutment operating mechanism and packingy ringadjustment mechanism outside of the casings, these parts are readilyaccessible for adjustment and repairs, while the parts contained withinthe casings are extremely simple and require the minimum amount of care.The pivoted abutment is readily accessible for adjustment or repair bysimply removing the cover 33 from the chamber 32.

For marine use each set should consist of three engines instead of twoas herein illustrated, and the piston heads, pivoted abutment and valveoperating gear would be positioned at 120O apart. This is desirableowing to the fact that with only two engines, should one of the enginesstop with its piston head between the steam outlet 34 and the exhaustport 23, the other engine with its piston head opposite and with itsvalve almost closed, could not be provided with su'ticient steam torotate the piston head of the first engine past its steam port. Forstationary use or for light service two engines, or even only oneengine, provided with a fly-wheel will be sufficient, since thediiiiculty just described might be overcome by manually rotating theengine or engines until the piston head of one of the engines has passedits steam port; but in marine or other heavy service, the set of threeengines will be required to eliminate such difficulty.

The pivoted abutment balancing levers, whereby the weight of the pivotedabutment is counterbalanced, are essential for high speed, and theselevers in connection with the compression spring, with means foradjusting it, together with the cam wheel rigidly mounted upon thepiston shaft andc engaging with the bell crank, .makes apid connectionwith the pivoted abutment whereby it is raised out of the path of thepiston head and at the same time permitted to engage therewith and withthe piston wheel suiiiciently to form a steam joint, thus insuringagainst undue wear of the parts.

In case of any accident to the balancing levers by which they arerendered inoperative during the operation of the engine, the piston headis so tapered as to pass under the pivoted abutment in either direction,in which case, the pivoted abutment is thrown upwardly against thehinged cushion plate and quickly returned to its position of engagementby the rebounding spring.

IVhile I have illustrated and described a preferred construction inwhich two cylinders are provided, it will be understood that myinvention covers an engine having one or more cylinders, the duplicationof cylinders being for the purpose of increasing power and eliminatingdead centers.

I claim:

l. A rotary engine composed of a cylinder casing with solid end on oneside and removable head at the other side, a horizontal shaft extendinglongitudinally through the center of said cylinder casing, a pistonwheel mounted centrally upon said shaft and being somewhat smaller thanthe cylinder, leaving a circular space between its periphery and ytheinside surface of the cylinder, a curved piston head rigidly mountedupon the periphery of the piston wheel in said circular space andadapted to engage the inside surface of the cylinder, its ends taperingto meet the surface of the periphery of the wheel, a pivoted abutmentrigidly mounted upon a pin in a recess of the casing, pivoted abutmentbalancing levers rigidly connected to said pin to hold the pivotedabutment in position to overcome friction, a spring plate mounted uponthe wall of the recess and engaging the head of the pivoted abutment toprevent steam from passing the pivoted abutment to the exhaust, a hingedplate mounted within the recess upon the recess cover, a reboundingspring interposed between said hinged plate and recess cover whereby acushion is foimed for engagement of the pivoted abutment and the pivotedabutment is caused to rebound, counteracting violent collision of thepiston head and pivoted abutment, an exhaust always open providing aclear channel for the piston head, on the inside of solid end and headof cylinder a circular channel of uniform dimension formed by a groovein the wall of the cylinder end and head respectively and by acorresponding recess upon the side of the periphery of: the wheel and asplit packing ring adapted to till said recess whereby a steam tightoint is formed preventing steam from passing from the circular space tothe center of the engine, and whereby the piston wheel is maintained inthe center of the cylinder thus causing uniform wear of the parts andreducing friction, substantially as set forth and for the purposesspecified.

2. In a rotary engine, a cylinder casing having` a removable andadjustable head and having on its interior two circular packing groovesadjacent to the periphery of the piston wheel, a piston wheel mounted insaid cylinder having upon each side thereof, adjacent its periphery, acircular packing recess each adapted to correspond with the adjacentpacking groove of the casing, a circular steam space between the casingand piston wheel, a packing ring of uniform dimension throughout itscircumference, adjustably secured in each of said packing grooves andprojecting and tting into said packing recesses, whereby the pistonwheel is maintained centrally of the casing, and a uniform engagement ofthe piston wheel with the casing, to form a steam tight joint excludingthe passage of steam from said circular steam space to the center of theengine, is obtained, a piston head on the piston wheel, a pivotedabutment adapted to co-act with the piston head, steam admissioncontrolling apparatus, an exhaust outlet, and a series of simultaneouslyoperable set screws directly engaging said packingrings and adapted toeffect a uniform adjustment of each packing ring and maintain saidadjustment against retreat at high pressure, substantially as set forthand for the purposes specied.

3. In a rotary engine, a cylinder casing in which a piston wheel isrotatably mounted on a shaft and provided with a piston head tapered ateach end to meet the periphery of the piston wheel lto permit of itspassage in either direction under the pivoted abutment engaging it underpressure regardless of the action of the mechanism for operating thepivoted abutment, said pivoted abutment, under which the piston head isadapted to advance during the rotation of the piston wheel, a cam wheelmounted on the shaft to rotate therewith, a lever mounted to move inunison with the pivoted abutment, a bell crank adapted to make Contactwith the cam wheel, a link connecting said bell crank and lever, and acompression device connected to said link, said bell crank being adaptedto be actuated by the cam wheel to raise the pivoted abutment out ofcontact with the piston head during the immediate advance of the pistonhead thereunder, and to allow the pivoted abutment t0 abruptly makeCon-v tact With the piston Wheel, substantially as set forth and for thepurposes specified.

4. In a rotary engine, a cylinder casing, a piston Wheel rotatablymounted therein, a piston head on the piston Wheel, a pivoted abutmentadapted to coact With the piston head, steam admission controllingapparatus, an exhaust outlet, the sides of the pivoted abutment andpiston head respectively being provided With inclined slots, packing nplates in said slots having beveled outer edges adapted to form by thepressure of the steam against them, steam-tight engagement tivelybetween the screw fastening and bevf r2o eled end whereby the packingplates 'are pressed outward against the Walls of said cylinder casing,substantially as set forth and for the purposes specified.

RUDOLPH F. SCHMIDT.

Titnesses z JAMES N. RAMsEY, CLARENCE PERDEW.

